From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 030E6C433DF for ; Mon, 20 Jul 2020 23:15:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB6C02065D for ; Mon, 20 Jul 2020 23:15:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726901AbgGTXPf (ORCPT ); Mon, 20 Jul 2020 19:15:35 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:45838 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726109AbgGTXPe (ORCPT ); Mon, 20 Jul 2020 19:15:34 -0400 Received: by mail-pl1-f196.google.com with SMTP id k4so9391865pld.12 for ; Mon, 20 Jul 2020 16:15:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=8MdlYlmqeapz+lWES5DzlofRg8ebONQpfWbq8TC/AcE=; b=HbV26hpIEIvZ0Cl3ngWRa9VLpuEj+ZSS9Zum0kh7e8rvkcbhWBcAIqxLQVbScCjM3q wcXb4CBobzClGy3OmxEc60frMsD9ZGviN8I5cvxomHesi2CyHGOQKxmbK5s2f7HpyvYN JM0U12f/gDSW/vLgUA+rRBU0MMIa31g/FRnLHJeNSBg/mJybTTUzi8bEw0cpNQkIU2jJ HYDZ+ZTF62pvdVw303oVJ8tntiB4oh+TWuc6qS2mMlAWSgRAYdDEHECSRPGZ99LUfoYH u2H4rrskGpDlqYTmv9ZTIQCLfPtJVFahTNnvO7Dw3/0aYz3CJc8pKJCoHCGxkd/SHxo8 9Ltg== X-Gm-Message-State: AOAM530ym1jDnBGKmw9pWv2KY1Z1Se4OgDTcXB+Ouh/nubPp0JNYUyl4 EdyyHkXT3VoHMRh83B+c+ns= X-Google-Smtp-Source: ABdhPJwbJoyhAgLqcBDDHOBujk/HlsFuCFkXaqar88knZbTDRJMGZtq/wh80vgsj1WSZEMX0aeVy0g== X-Received: by 2002:a17:90a:bf02:: with SMTP id c2mr1625764pjs.114.1595286933772; Mon, 20 Jul 2020 16:15:33 -0700 (PDT) Received: from ?IPv6:2601:647:4802:9070:81fd:84d6:3c38:f7ef? ([2601:647:4802:9070:81fd:84d6:3c38:f7ef]) by smtp.gmail.com with ESMTPSA id y27sm16821780pgc.56.2020.07.20.16.15.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Jul 2020 16:15:32 -0700 (PDT) Subject: Re: [PATCH v15 7/9] nvmet-passthru: Add passthru code to process commands To: Logan Gunthorpe , Christoph Hellwig Cc: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, Keith Busch , Jens Axboe , Chaitanya Kulkarni , Max Gurtovoy , Stephen Bates References: <20200716203319.16022-1-logang@deltatee.com> <20200716203319.16022-8-logang@deltatee.com> <20200720141606.GF4627@lst.de> <5cc390cf-9b0b-b48b-7447-37934be51ee0@deltatee.com> <2dc39232-4042-1f93-3dcc-3266e70cf6f0@grimberg.me> From: Sagi Grimberg Message-ID: Date: Mon, 20 Jul 2020 16:15:31 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> Thanks for the review Christoph. I think I should be able to make all >>> the requested changes in the next week or two. >>> >>> On 2020-07-20 1:35 p.m., Sagi Grimberg wrote: >>>> >>>>> I'm still not so happy about having to look up the namespace and still >>>>> wonder if we should generalize the connect_q to a passthrough_q. But >>>>> I guess we can do that later and then reduce some of the exports here.. >>>> >>>> That is a neat idea! should be easy to do (and we can then lose the host >>>> xarray stuff). I don't mind having it on a later patch, but it should be >>>> easy enough to do even before... >>>> >>> >>> I sort of follow this. I can try to work something up but it will >>> probably take me a few iterations to get it to where you want it. So, >>> roughly, we'd create a passthrough_q in core with the controller's IO >>> tagset and then cleanup the fabrics hosts to use that instead of each >>> independently creating their connect_q? >>> >>> Though, I don't understand how this relates to the host xarray stuff >>> that Sagi mentioned... >> >> passthru commands are in essence REQ_OP_DRV_IN/REQ_OP_DRV_OUT, which >> means that the driver shouldn't need the ns at all. So if you have a >> dedicated request queue (mapped to the I/O tagset), you don't need the >> ns->queue and we can lose the ns lookup altogether. > > Thanks, that helps clarify things a bit, but which xarray were you > talking about? The patch from Chaitanya See "[PATCH V4 2/2] nvme-core: use xarray for ctrl ns tracking"